Carbon Bicycle Forks: Cautions, Facts and Misconceptions

On my post about the 2011 Jamis Coda Sport, a reader left an interesting comment about the catastrophic failure of carbon forks. When I was writing the post, it never occurred to me that the carbon fork, which I wanted, would be a problem for someone else.

Not long ago, I was shopping for a carbon fork for a road bike. I did a lot of research, not only on various brands, but on the safety and durability of carbon. Afterward, I felt confident enough in carbon (as a material) to purchase a carbon fork. I’m not a weight weenie. I just love a carbon fork’s ride.

I learned some interesting things. For instance, most of the “unexplained catastrophic carbon fork failure” reports are located on personal websites or in bike forums. There aren’t well-known consumer or professional cycling websites warning consumers about the “dangers” of carbon forks.

Any fork failure can cause serious injuries. Forks made out of every material have failed without warning. If steel or aluminum always gave warning, no one would have their fork fail while riding. I can’t see how a crash from one type of failed fork would necessarily cause more injury than another. Just like carbon, a failed steel or aluminum fork would cause a loss of control. The terrain and bike’s speed would have as much effect on the severity of a cyclist’s injuries as the failed fork.

Fifteen years ago, dire warnings were made about aluminum forks. In spite of those warnings, the aluminum fork failure rate isn’t significantly worse than any other fork material.

One of my bikes has an aluminum fork. When I bought it I was told that it was more likely to crack and fail than carbon or steel. For financial reasons, I settled for the aluminum fork. Tens of thousands of miles later, the recently inspected fork shows no sign of wear.

“So, I’ve been noticing that the front brakes of my road bike were acting “grabby” in that the front would shimmy pretty badly just as I’m coming to a stop. The rims felt a little sticky, maybe some Gatorade got on them and it hasn’t really rained in a while. I cleaned the wheels last night and rode into work today. It was still bad, but didn’t seem as bad. This has been going on for a week, I didn’t think anything of it. I decided to not ride after work and just come home, coming down the driveway, the grabby-ness was really pronounced, so I figure that the brake pads must be contaminated with something.
When I took the wheel off, my heart skipped a beat. Without much effort, this is the result:

It was hanging by no more than 2mm of steeel. I shudder when I think of the roads I was about to go on, including one really bad bump at the bottom. I don’t think it would have held together and when you lose the front like this, it’s going to be bad.

The shimmy was the wheel moving back and forth due to the fork leg being fatigued. There hasn’t been any accident damage since I put this fork on the bike. The crack was almost all the way through, starting from the BACK of the fork leg.”

This cyclist had no reason to suspect that the bike’s behavior had anything to do with the fork. The same thing could have happened to anyone. There are as many misconceptions about steel and aluminum as there are about carbon.

VeloNews technical writer Lennard Zinn, a frame builder, former U.S. national team rider, and author of several books including two successful maintenance guides wrote an article entitled: Technical FAQ with Lennard Zinn: Carbon Forks.

Here, Zinn and manufacturers answer questions about rider weight limits, the lifespan of carbon forks and their durability.

“Question: What is the state of thinking on the life-span of carbon forks? Will they last forever, show signs of wear or should they be replaced after some span of years/use? I’ve had a Time fork in my old Merlin since 1998. It’s lived through a few race crashes and seems as good as ever, but I still have trouble regarding it as something as long-lasting as a metal component. Thoughts?–Jon”

Manufacturers’ replies:

From True Temper:

“We are confident on the long-term durability of our forks because we test far beyond the ASTM test standards for fatigue life on forks.

We have two types of fatigue tests:

1) ASTM
2) Ramped load testing

ASTM standards call for a load of 170 lbs. applied perpendicular to the steering axis, both pushing and pulling for 50,000 cycles without failure.

At True Temper, every Alpha Q model is tested to 250,000 without failure before a design is considered acceptable. Also production models are tested periodically for quality control.

True Temper’s own test is also used on every new model and in routine quality checks. Our test is a ramped load, meaning the load is increased periodically until failure occurs. Starting at 180lbs, the load is increased 45 lbs. every 5000 cycles. Every fork will eventually break. Strong forks will last more than 10,000 cycles with a load of 270 lb. But our minimum standard begins at over 15,000 at 315 lbs. for road forks and 18,000 for cross forks and tandem. But our production forks are stronger than that, often going into the 20-25K range and beyond at loads 0f 360-405 lbs.

Obviously, crashes are uncontrolled events and it is not easy to guess what loading was applied to a component by the speed or violence of the crash. After any crash it is important to thoroughly inspect the frame and components for visible cracks, dents, and bends. An Alpha Q fork that has been damaged (usually evident as a crack) should be replaced.

–Bert Hull
True Temper Sports”

From Kestrel:

“On the lifespan issue, of course the person should contact the manufacturer regarding specifics on the product in question. For carbon forks in general, there should not be any limited life span, as carbon composites themselves are not subject to fatigue failures as metals are. So the fatigue life of a properly made carbon composite is “infinite”. Example, in Kestrel’s case, our forks (as with all our carbon products) have a lifetime warranty and are designed and tested to last a “lifetime” of use for the given product…

–Preston Sandusky
Sand Point Design (Kestrel Bicycles)”

From Easton:

“There are two failure modes that could cause a fork to fail, fatigue or impact. Questions about life span are really questions about fatigue life. How many cycles can a fork survive before it is tired and worn-out? The good news is the fatigue life of carbon fiber is immensely more than that of metals. While the writer expresses concern about his carbon fork lasting as long as a metal component, there is nothing to worry about in terms of fatigue life on a composite fork.

The most likely cause of failure for a composite fork would be impact damage sustained from crashing. Most of the time any damage to a fork from a crash will be visible. Cracks can be seen. We would recommend that the fork be periodically inspected visually at the drop out area and along the fork legs to look for cracks or depressions in the material. Any fork that shows signs of cracking should not be ridden and replaced immediately.

In general terms, a component made from carbon fiber will far out-last a component made from metal.

–John Harrington
Easton Sports”

A Technical White Paper on frame materials written by Calfee Design (founded by the owner of Carbonframes – which made 18 frames, ordered by Greg LeMond, for Team Z) explains more about carbon use in bicycles.

“Carbon fiber frames first appeared in the mid 1970’s. The number increased in the 1980’s as more carbon fiber frames and a few components began to trickle into high-end bike dealers and parts catalogs. But these efforts were mostly limited attempts to save weight and often lacked careful engineering and commitment by the manufacturers. The lasting impression of most carbon fiber products was that they were quirky, flexible, fragile, and very expensive.

Over the past fifteen years, several more innovative carbon fiber framesets have entered the market. These have successfully challenged metal frames in two areas of performance – weight and ride comfort. But even some early versions of a few brands also had a poor record of reliability. Multiple warranty returns to fix cracks, loose dropouts and other unbonded metal parts were common…

Composites have made many advances since the mid ’80’s. Resins, fibers, and epoxies are a lot stronger today. What is more important, understanding how to use these materials has increased tremendously, due in part, to development of sophisticated analysis programs. Composites are more than high-tech weight savers; they are superior structural materials that are revolutionizing the way we build bicycles. A well-designed composite frameset performs better than a metal one. After taking some tentative steps, it has become a viable material in the bicycling industry. A few manufacturers have taken the necessary steps, and have a relatively firm grasp on the capabilities, potentials, and limitations of composites….

Carbon fiber exhibits the most desirable performance characteristics of any of the frame-building materials explored to date. It can be designed to be laterally stiff under heavy pedaling forces and still be light. It can absorb road shocks well, and still handle crisply while delivering undiminished applied pedal power to the drive train. It can be durable and not subject to fatigue failures while remaining strong enough to stand up to unexpected impacts and torsion forces. It can lend itself to attractive finishing and resist corrosion or attack by the elements. And it can be formed in an attractive, functional way allowing it to move through air resistance easily.”

If carbon forks are so prone to catastrophic failure, why are there no high profile carbon bike or fork class action lawsuits circulating on the Internet? In a litigious society like the U.S. (i.e one where people frequently sue one another), at least one carbon fork manufacturer would have been sued out of existence by now. Instead, many carbon fork manufacturers offer a lifetime warranty on their forks. Just from a business standpoint, if the failure rate was high, they would go out of business.

Even if you hate or fear carbon, this video of stunt riding on a carbon road bike is fun to watch. It demonstrates the amount of abuse carbon can take.

Bottom line: regardless of frame and fork material, always maintain your bike. Periodically, have an authorized dealer inspect it. Exercise caution if you ride hard or crash. Never overlook the inherent danger in activities involving equipment. Take proper precautions to avoid unnecessary risk and don’t be immobilized by fear of equipment failure.

Isolate, thanks for this well-researched post. I never understood the hysteria over one frame material or the other in terms of catastrophic failures – except, maybe bamboo. I still have to be convinced about the durability of bamboo.

I don’t think the issues is quality of material so much as durability of a material after a wreck. My Kona chromoly fork is pretty banged up from years of commuting, I can’t imagine that a carbon fiber fork would still be holding up after a few wrecks and close calls with the same number of impacts that my steel fork has taken. That being the case, of course there are lifetime warranties and a noticeable lack of class-action lawsuits, since a fork failure due to a wreck puts the rider on the line, not the manufacturer. Not to mention, a metal fork will give you some warning before failure where as a cf fork will probably be catastrophic like some of the pictures of fork+squirrel floating around the net.

In my own view, no one has proven that carbon fails catastrophically, while steel and other materials do not. What you see online is scary looking pictures due to the fact that carbon looks different from steel when it breaks apart.

If you look at the broken steel fork photo above, you will see that it has snapped apart, rather than bending, as many people claim is typical of steel. The rider had no warning before this steel fork failed – and the bike was never involved in a crash, so he had no reason to suspect a problem with the fork. The same thing could happen to an aluminum fork.

Carbon forks have been ridden, without incident, after crashes – although manufacturers recommend replacing them after a crash. The main difference between carbon and steel, in terms of sudden failure, is that the rider can’t inspect a carbon fork properly due to the lack of visual cues for certain types of damage. After a crash, a carbon fork should be taken to an authorized dealer for a thorough inspection – which involves testing – not just a visual inspection of the fork.

I don’t see any inconsistency in what I wrote. The rider’s problem was related to braking. He thought that the rims were “sticky.” Here is what he said:

“So, I’ve been noticing that the front brakes of my road bike were acting “grabby” in that the front would shimmy pretty badly just as I’m coming to a stop. The rims felt a little sticky, maybe some Gatorade got on them and it hasn’t really rained in a while… so I figure that the brake pads must be contaminated with something.”

He had no reason to believe that the mechanical issue he was dealing with was related to the fork. Can you explain to me why you think that an unidentified braking problem is warning that a fork is failing?

“Can you explain to me why you think that an unidentified braking problem is warning that a fork is failing?”

It is an indication a fork could be failing, your brakes don’t just suddenly start dragging unless something is wrong, such as a broken spoke, a bent rim, or a bent fork. It should be cause for inspection, however not everyone can be expected to understand the failure mode, neither did this person. Even though he failed to understand the failure mode, his fork did NOT have a catastrophic failure. He only noticed once he took the wheel off. In contrast, a carbon fork would more likely just have snapped and the rider would have crashed. This then does nothing to further your argument, it actually proves how metal forks can be safer.

By the way, in many cases a metal fork that is failing is not crash inducing because when you apply the brakes the break closes up allowing you to safely come to a stop.

Another problem is that you don’t understand how metal fails. It does not just “snap off” as you claim. The metal can fatique and eventually break. Metal can also yield to certain excessive pressure and assume a new shape. Carbon does not, it either just snaps or it doesn’t. The failure mode of the steel fork as described underwrites this, the fatique was slowly increasing the damage until only 2 mm of steel was attached. That is not snapping off.

Last point is that the manufacturer “True Temper” you quote is misleading. Since carbon fiber does not fatigue like metal does (Titanium actually does have an infinite amount of movement cycles, as long as the force applied is below a certain threshold where it is not forced to yield, unlike Aluminium which will fatigue eventually, regardless of the force applied). It is pointless for the manufacturer to test carbon for fatigue and proudly showing strong test results in that regard for carbon is misleading and does nothing to test sudden catastrophic failure.

When the front brakes suddenly act “grabby” and a shimmy develops, potential problems include fork/frame alignment, rim and hub issues, and headset problems. A shimmy is usually not associated with a braking issue. Any time either of these problems appears, the whole front end should be looked at, but when both of them occur at the same time, most people would not dismiss the issue as solely brakes. I am not saying that I would have immediately realized the risk of such a serious problem, but I think you can say that he had warning for the previous week. One cannot conclude that it was catastrophic just because the owner incorrectly associated the symptoms with a brake issue. It sounds like good design and manufacturing trumps materials.

I don’t disagree with your points, in general. However, I think that your conclusion about the “shimmy” warning of a potential fork failure is a stretch. As you said yourself, potential problems could include “fork/frame alignment.” Even if your fork/frame are out of alignment, this is not a warning that your fork will snap in half in a time period as short as a week. It only looks that way to you because you are viewing the problem in hindsight.

Where we agree is on the point that there were symptoms of a potentially serious problem and he should have had them checked out right away, instead of continuing to ride the bike. He obviously didn’t have enough experience to evaluate the bike’s condition properly. But, millions of cyclists do the same thing as he did – all the time – and their forks don’t snap in half as a consequence.

“It sounds like good design and manufacturing trumps materials.”

This is very true. All materials will fail under the right conditions, and sometimes without warning – or any symptom obvious enough to point to the precise location of the problem. Good design and manufacturing can reduce the odds of unexpected material failure.

Ironically, after reading your post on carbon forks and deciding on a 2011 Specialized Sirrus Elite, (a very nicely finished aluminum hybrid bike with a carbon fork), I attempted to place an order for the bike yesterday. The first bike shop informed me that they were completely sold out and that I should instead order either a 2011 Sirrus Elite Disk or a 2012 Sirrus Elite. Sadly, the 2012 model was $110 more, even with downgraded components, while the 2011 Elite Disk had an aluminum fork, offering a much inferior ride. When I visited a second shop selling Specialized bikes on the hope that they still might have a 2011 Sirrus Elite in inventory, they explained they just that morning had shipped all of them back to Specialized. The manufacturer had recalled the 2011 Sirrus Elites because its carbon forks were failing all too often! Hopefully, it was just a bad production batch, but it is disquieting nevertheless. After reading your review of the 2011 Jamis Coda Sport, though, I altered my hybrid bike purchase decision and ordered one, carbon fork and all.

There are no recall from specialized since 2009, and even before that none were due to carbon forks.. such recall is a f’ing LIE.
Besides that, the sirrus fork is also sharred by the secteur and the roubaix… there are also no recall on those.

I bought a Sirrus Elite 2011 second hand 6 months ago. Before I bought the bike I read up on what to look for with carbon forks as I had never owned a road bike, or carbon forks. I am not a qualified bike mechanic but after very close inspection there were no cracks in the lacquer (which I assume is the first place a carbon fork would show signs of fatigue) de-lamination of layers or cracks in the carbon underneath when the fork was loaded from the front and rear. I was happy that the forks were flexing enough to show any issues with the fork.

I was cycling 6km per day in London to the station, the roads are not the smoothest but no worse than any other town or city. In London you often have to brake hard because other road users, drivers & pedestrains tend not to look as much as they should. I rode the bike for 4 months with no problems but I started to notice a brake shudder only when applying the brakes very softly, which I also thought was an issue with the brake components. I cleaned and checked the forks, did another load test and saw no new cracks or anything abnormal. A month later I had to brake heavily when a pedestrian stepped out in front of me, it was damp, I came off and was uninjured luckily but as I was falling I heard a crack. One side of the forks cracked around the top of the left leg completely and the right leg had cracks in the lacquer. The pedestrian just seemed to pause for a second then RAN off when I was on the ground in the middle of the road so thanks for that whoever you were!

I know that some will say I should have taken the bike to a bike mechanic to have the fork checked out but I can’t see how they would have tested it any differently.

I would never buy a replacement carbon fork, I don’t feel that they are worth the small weight saving. I will be replacing it with aluminium or steel, which I feel will not fail after heavy braking and will show signs of fatigue in the paint. Although not a cause for coming off the bike the fork still failed which im very unimpressed with. For commuter use carbon isn’t worth it, especially when the bike will likely be stolen eventually!

Interesting to read the link below about the brake boss becoming loose, maybe this was the shuddering issue I felt but is unrelated to the forks cracking.

I had a very similar experience with my 2009 Specialized Roubaix Comp. I was riding at about 19.5 mph on a flat and hit a small bump in the road and the fork broke clean off on both sides. I think the first break was where the neoprene inserts are placed on the left side, and the break was higher up on the right side of the fork. The Specialized Carbon Fork is dangerous in my view.

I came upon this blog post after a friend had a serious accident when her Specialized carbon fibre fork suddenly cracked during a ride (“shattered” as she and her husband described it). I believe hers was a 2009 or 2010, but I don’t know the specific model. She, nor her husband riding behind her, noted hitting any major bumps. They were riding on a paved city-road bike lane.

She was knocked unconscious, and received numerous injuries to her face, including teeth being chipped and shifted out of position. Thankfully, there don’t seem to be any long-lasting injuries, aside from the teeth which need re-alignment. I imagine the helmet helped, but as it was an in-traffic incident, it’s not much of a stretch to say that she could have been killed.

It’s certainly enough to steer me away from Specialized carbon fibre forks, and, as I’m kind of angry about it, I won’t be purchasing any Specialized products at all.

Here’s the specialized recall page posts where you’ll notice numerous 2011 & 2012 model fork recalls, though none mention the kind of failures we’re noting here (and it seems that perhaps they should be adding more to this list):http://www.specialized.com/us/en/support/safety-notices

Actually the account of the steel fork does not portray unexpected or catastrophic failure. He noticed a “grabby wobblie” feeling for awhile before takig off the wheel, at which point the fork came apart. The wheel was probably holding the fork tang in place to some extent.

That said, I use both types. On my road bike I have a steel fork, and it feels great. I have two cross bikes, one with steel straight bladed fork, one with the Easton EC 90. In terms of ride quality the steel forks win hands down. You can feel the road, but it’s not a numbing sensation or anything. The steel fork of the ‘cross bike is much more rigid, it tracks better than the EC90. Huge downside of steel forks? It weighs about a one and a half pounds more than the EC90.

So, aside from the significant weight savings, which is important in cyclocross, (and racing in general) I don’t see any advantages in carbon forks.

You’re right. I looked it up and a recall on certain Specialized bicycle forks was just issued (August 2011). However, the recall is due to a manufacturing defect related to the brake boss, not catastrophic failure of the carbon forks.

For anyone who may be affected by this problem, the recall notice says the following for Carbon Forks On Certain 2011 Model Year Specialized Bicycles:

“The brake boss housed in the Advanced Group carbon fork on the specified Specialized bicycles can disengage from the fork and allow the brake assembly to contact the wheel spokes while rotating, posing a fall hazard.”

I had a 2009 carbon Trek Madone 6.5 with Bontrager Race X Lite carbon fork and it catastrophically failed on me with very little riding and meticulous care taken with the bike…it had never even fallen over much less crashed. I was riding on good surface with no obstructions and the carbon imploded. I have 2 broken and 1 compressed vertebrate from that crash 1 year ago. Absolutely no warning with it. Can send photo if you would like to send an address to send one to for posting to this article. Class Action could very likely happen in the near future as in my visits with attorneys and carbon fibre experts around the country, it is scarey how common place this carbon failure is. It appears bike manufacturers are excellent at fighting each case in court as hard as possible and settling just before a full trial….getting confidentiality agreements signed and it disappears from the public.

I would be interested in seeing a photo of your bike and any supporting documentation you have related to your claim that catastrophic failures of carbon are very common. I will e-mail you with an address where you can send it.

I sent an e-mail, a few hours after you posted your comment, to the address you submitted with your comment. If you didn’t receive it, check your spam folder. You can also contact me via my blog’s contact form (click on the contact link at the top of this page). I’m interested in learning about what happened to your bike and how prevalent this problem is.

Hi.
Well, on October 23, 2011, I was riding my 5 months old 2010 Fuji Cyclecros with a Carbon Fiber Fork on a smooth road and they cracked on both side (one side much more than the other though), the front wheel shift, locked, and i went to the road in 15~16 mph! All I could hear before was an unusual noise for a second or so and even though I lower my cadence to see where the noise is coming from, it didn’t last more than a second or two. I broke my nose, several teeth, sprang my both wrist, torn my upper lip and bruise most of my face and my hand.
I’m sorry, but this is a catastrophic failure!
I know that Carbon Fiber is the thing to have etc. but we cannot ignore the fact that on occasion, THOSE FORK BRAKE FOR NO REASON AND WITHOUT ANY WARNING!!!
email me and I’ll email you the pictures.

I had a crash into a curb at night while seated at approximately 10 mph on my Litespeed Vortex ti bike with a Reynolds Ouzo Pro full carbon fork. I went over the bars but was most just dusty but no other harm done. I got back on the bike and started riding again to notice that my head tube had a major crack in it. This was two years ago. I finally had the frame welded and have carefully inspected the fork for damage. I cannot find any with the naked eye. What can a LBS do that I cannot do myself as far as inspection? I am in the process of buying another fork only because everyone says to replace the fork after a crash. I personally know of two people that have had carbon fork failure related crashes, however I do not have all the info about the crashes as I was not there. I am very tempted to ride the original fork but everytime I do a 45mph decent it will always be in the back of mind that I am riding a previously crashed fork.

It is generally recommended to replace a carbon fork after a crash because of the difficulty of ensuring the integrity of carbon fiber after it has sustained an impact. You can test the fork yourself, if you are willing to take the risk of missing a problem and having the fork fail. As for your LBS, the mechanics should be trained to inspect carbon for damage — and they have more experience at finding damage than you do since they see more forks.

If you want to test the fork yourself, there are some resources which can help you to test it properly. According to a carbon inspection document written by Trek, you should do the following:

– Check for scratches, gouges, or other surface problems.

– Check the part for loss of rigidity.

– Check the part for delamination.

– Listen for unusual noises.

The document describes how to perform these tests. There is also a video which shows you how to inspect a carbon fiber part for damage.

If I were you, I would take the fork to your LBS and let them inspect it. You can make a decision based on their advice. But, the safest thing to do is to replace the fork so you will have peace of mind when you ride.

I’ve ridden countless centuries and have interacted with hundreds of Cyclists and have never met anyone who has encountered a Catastrophic failure of a Carbon fiber component, including Frame and Forks.

In fact, I’m the only one (unlucky huh)? I was riding my $7K roadbike on a fast group century, we were on a smoothly paved main road when I heard a “Poink” sound and felt it through the Handlebars. The next thing I knew, a Paramedic was kneeling over me, I had been unconscious for about 20 minutes. I found out sometime later that my Forks had sheared off a few inches below the crown. At 21.4 mph, according to my Friends Garmin 705. I dove head-first into the Tarmac.

I suffered severe head trauma, broken neck, 5 crushed vertebrae and a few other broken Bones.
7 Days in ICU, 7 weeks in Hospital, 5 months in a Body Cast, 6 months off work, $450K in medical Bills plus 8 months PT later I’m back on the Bike.

Check your Frames and Forks regularly, irrespective of material, don’t take chances, you can’t wind back the clock. Catastrophic failure can change your life for ever.

unfortunately, i believe those failure fall under “product liability”, which is very difficult to prove, or very difficult to find a lawyer to take the case…
I’m still very surprise as how the fork fail all of a sudden.
my next bike will be all carbon fiber BUT with a custom made steel fork. yes, this fork can fail as well, but much, much slower with lots of warning.

Switched out a full carbon fork for a straight bladed steel fork. (salsa). The steel fork allows a little more minor road feel to come through, though bigger hits are deflected much better than the carbon fork. Overall, the steel feels better. It weighs 800 grams, the carbon is 450 grams. By the way, my frame is steel, columbus foco . Also, I don’t race, and could stand to lose 40 lbs, so, bike weight is moot. I think racers should all ride carbon, but most folks riding for fitness/pleasure, could enjoy riding just as much, if not more, on steel.

Hi,
this article is a light in the dark…
i loved it!
will be interesting for me to know your opinion about the carbon FACT recalls of 2011 and 2012 by Specialized company…
Front brakes seems to leaves the fork like a fatigue fail, so if for composite material talk to fatigue fail is uncorrect what it cuold be…?

“The rims felt a little sticky, maybe some Gatorade got on them and it hasn’t really rained in a while”

so the guy left his steel bike out in the raise according to his post. metal corrodes so of course frame or fork failure is eminent
carbon fiber is incredibly strong but its to tough
try hammering a nail into a steel head tube the try it on a carbon head tube and see which one is effected the most

Sorry to bump an old thread, but this has been the most comprehensive discussion I have seen. The carbon fork on my 2006 Fuji Roubieux failed in spectactular fashion two months ago. I was riding downhill when the fork delaminated from the crown. I was wearing a helment, which probably saved my life. I didn’t come off as badly as some of the folks above (I hope you are recovering from your injuries) – compression facture of my spine at L1, broken right wrist, and broken left thumb.

Fuji is evaluating whether to replace my fork under warranty, but frankly I don’t think I would trust the replacement fork. I am an avid road and mountain biker – but after this accident (which could have been much worse if I had been pitched into traffic instead of the ditch) my wife is worried about me riding at all.

Trent
Sorry to hear about your crash. I represent a cyclist whose carbon fork failed without warning and sent him over the handlebars as well. I’d be interested in hearing more about your incident and your experience with Fuji.

When I read of sudden frame or fork failures with no warning or previous impact, it reminds me of some derailler vs spokes repairs we see at our LBS. Customer was “jra” when the derailler suddenly hit the spokes and broke off, imploded, killed the wheel, bent the derailler hanger or some combination of those. When examined, the derailler shows obvious signs of scraping on the ground, usually parallel gouges. When first asked, they most often insist the bike has never been crashed or fallen over. When shown the scrapes, many remember the incident that caused it. I don’t believe that most of these people are being deceptive. The incident was to them, minor, and so doesn’t get remembered. Still the damage is there. The derailler hanger or derailler is bent in toward the wheel waiting for them to shift to their big cog under a load to wreak its havoc. I wonder how many of these “sudden” carbon failures can be attributed to an similar unremembered incident.

I’m not implying companies never make defective parts, only that all is not what it seems at first read. Parts and frames fail for a reason and in my experience (20+ yrs) the signs are there. The question is whether they get noticed.

Quite interesting I thought, so I decided to check if my recently purchased bike had any recalls…and indeed it did, for it’s carbon fork (Giant defy advanced 2), but only in the US, not in the UK. Not a nice feeling though, and it certainly makes you question why you would want to take a chance on carbon fibre. Lovely bike though. Perhaps bike companies should make crash data/videos available like they do with cars.

from reading around the internet, i have a feeling that carbon fails more often than we would like to admit, but that manufacturers do what they have to do to keep it quiet. just like the pharmaceutical industry also knows how to keep certain things quiet. and this is potentially one of the reasons why i don’t hear about law suits

i’ve ridden 100% carbon (integrated handlebars, frame, fork and wheels) for years and yes i believe carbon is the toughest. but strength is not the issue, failure is. carbon still fails, probably as much as the other materials

my impression is that the tests don’t account for real life riding situations: for example, looking at the tests described in your article, i can’t really see how these represent what my fork goes through when i am actually out training. they seem to blatantly overemphasise one dimension in order to completely ignore smaller but very significant others. the braking tests on carbon clinchers is another good example of test inadequacy (roll 12 seconds to reach 50km/h, brake from 50 to 0km/h in 4 seconds, repeat for at least … cycles): the wheels pass all the testing but will fail the very first time you apply the brakes out on the road

my other thought is that maybe some people don’t really know how to mount carbon components on a bike and then these components fail,
or maybe carbon is too much of a challenge for certain bike parts from a manufacturing point of view (reproducibility of specs (specifications) during manufacture)

and even though it’s strong it seems we have to look a lot more after carbon than any other material if our bike is made of it

Solid dialog. Intensely interested in this subject as I was involved in an incident albeit not my front fork. A friend of mine and I were at a mid point of a favorite hill riding side by side … me to the road edge. I was still in the saddle and Jeff had just come out. On his first right down stroke his fork snapped (right leg of fork) just below the head tube connection causing him to fall into me and us into (fortunately) into a heavy sage grassed shoulder at a very low speed. I will never forget the loudness of the ‘snap’. He was riding a an early Giant Defy (will verify the year) which had shown moments of fork chatter … apparently a common problem with the early models. I still ride on my carbon fork but inspect it vigorously. At some point, I will probably move away from carbon.

I posted earlier about my fork failure on my 2006 Fuji Roubieux. After my initial discussion my Advanced Sports International (the Fuji folks in the US) in mid-October where they wished me a speedy recovery and told me they would evaluate the failure I have not heard a word. I have tried to contact ASI/Fuji through the bike store, through their website, and through certified mail. The bike store tells me that their usual “warranty guy” has been told not to talk to me and that any communications must come from a higher power. I am becoming very frustrated with the process as they have had my bike since October and seem to be dodging my efforts at communications.

I offer the suggestion the bike industry should hand out the SHILL AWARDS. Many categories could be given a trophy.. a replica of the ‘lance’ in injection mode would be fitting. I’ll nominate YOU as the first recipient of the CARBON FORK “shiller”… hands down.

What carbon is in essence.. is a technology whereas peasants over the pond can fabricate sans the expensive machinery required by metal manufacture. Donating their health… their environment.. for the wage that allows living in a rabbit hutch.. just slightly off the ground.

I recently purchased a fixed wheel bike. After a few days a heard noises coming from the headset there was also some movement. The bike has an aluminium frame and carbon forks. On closer inspection I noticed that the front wheel was closer to one side of the wheel that the other. I returned my bike to the dealer who agreed that this was so and contacted the manufecturer who agreed to change the forks. After looking up the bike manufactures website I saw that some models, not mine had be recalled due to faults with the forks and owners were compensated by a small amount financially.
When I emailed the company the refused to compensate for me as the others were a different model. Am I right in assuming that the problem with my forks could eventually result in a failure?

“Am I right in assuming that the problem with my forks could eventually result in a failure?”

This is a difficult question to answer. Sometimes a particular fork is recalled because of a manufacturing problem, or occasionally due to a design flaw. This does not mean that other fork models made by the same manufacturer are also defective. They may have been manufactured at a different time or in a different location, and may serve you well for many years.

The best way to put your mind at ease would be to have your current fork inspected by an independent party. Although this will not be a guarantee against eventual failure, it will give you insight into whether any noticeable problems exist.

Keep in mind that it is not easy to test a carbon fork. It can be checked for damage, and certain types of defects would be visible to someone who has a lot of experience working with carbon forks. In most cases, such an inspection is adequate and will ensure a safe ride.

If there are any bicycle builders in your area, you may want to consult with them, particularly if they sell carbon forks with their frames. Builders often look at frames and forks differently than mechanics and they may be able to provide you with some guidance.

There are never any guarantees with bicycles — or any equipment for that matter. You can either ride with your current carbon fork and have it professionally inspected on a regular basis, or purchase a fork made of another material — aluminum, for example — to avoid worrying about your carbon fork failing.

I’m a few years late on this discussion. These are such refreshingly rational comments, that I want to give my $0.02. Better late than never!

My wife and I are having a titanium tandem built. Just put down the deposit with a terrific builder and are reviewing spec. Since we’ll be touring at a leisurely pace occasionally in remote areas like SE Asia, I assumed a steel fork would be a slam dunk. Not so fast…..

The builder hates weight in the same proportion as he loves carbon & ti. Nothing wrong with that. High performance drives his approach. I appreciate that. The cynic in me thinks he may also enjoy profit margins at some level.

So here’s why I’m holding firm with steel. I spoke with the two carbon manufactures (Whiskey and Evne). They make beefy forks that you can find on several tandems. When I ask if I can install on a tandem, then answer is a resounding “NO”. Does that mean the forks are too frail? I don’t think so. My wife and I are a relatively light team at 280 lbs. The real translation is: If you install on a tandem and the fork fails, don’t come crying to us- we told you so. For the rider this is true liability if you find yourself on the losing end of a catastrophic failure. In legal terms, you would receive a notice of “sit and spin”

The interesting aspect is why carbon forks continue being pushed- even in proscribed applications like mine. I don’t know. What I do know is steel, though slightly heavier, can be engineered for tandem use, plus I don’t have to visit a bike shop for a stress test if an airport baggage handler carelessly tosses my bike bag to the gorilla just behind the baggage carousel. (sorry for the 1970’s reference!)

I haven’t read through all 48 comments left here thus far, or even the entire blog post, so forgive me if the following points have already been made. Also, please forgive the random sequence and kludgy HTML formatting. WordPress doesn’t make editing this shit easy.

1. Your example of “unexpected steel fork failure” is of a cyclist who didn’t so much as look at their frame and fork regularly, let alone when it begins to perform poorly. They rode on a failed steel fork for a week! The failure may have been unexpected, but it certainly was not without warning. The owner was simply too daft to heed said warning.

Despite all that, the fork kept this twit alive for a week. I daresay the outcome would have been less favourable on a carbon, aluminum or carbon/aluminum fork with comparable damage. In fact, given the mechanical properties of the materials, it is likely that the rider above would have crashed the second the damage occurred. None of this “grabby brakes for a week” shit. Instant failure, and likely, instant injury or death.

Bullshit. Not only did it not snap as you claim, but was in fact still in one piece when the rider noticed it, albeit a loose one (“It was hanging by no more than 2mm of steeel (sic).”) What I see in the photos (plural, as you didn’t include the closeups) is corrosion at the start of the tear, and several jagged rips that mostly follow the contours of the crown lug until the “driveway” failure.

More bullshit. Grabby brakes out of nowhere lasting for a week is a warning. You’re really torquing your language to suit.

2. One photo in the original forum post shows that the fork “tube” is seamed, or put differently, a flat piece of sheet metal formed into something that outwardly looks like a tube.

This is not a failure of steel forks per se, but rather a failure of a cheap Chinese “tribute to bicycle fork”. A poster replying to this guy also rightly points out that chrome plating is a catalyst for corrosion. In other words, this hipster dingus would have had no problems if he was running his original painted fork. Another (almost) victim of fashion.

And again, it still held together long enough for him to save his own life.

3. Carbon fibre is an amazing material, as are aluminum and steel…but they aren’t the same. For one, steel can flex and rebound while the other two cannot. This is why we don’t make springs out of aluminum. Don’t believe me? Slightly squeeze an empty Pepsi can, and then do the same with an empty soup tin. Which one has a dent in it? Exactly.

In the same vein, carbon fibre is very strong…in one direction only. This is why you can bunny hop a 100% carbon fork (when undamaged, at least) without issue, but the same fork will snap like a twig if the same rider stands on it while the bike is on the ground. Carbon fibre is also highly intolerant of surface flaws (READ: scratches).

4. Why would manufacturers, or the magazines and websites who depend on their advertising dollars, publicize fork failures? Bicycles and parts aren’t regulated in like cars, leaving safety testing in the hands of bike makers (so-called “self-policing”). Larger manufacturers have zero interest in putting facts out there, a shame because they’ve done destructive testing on thousands of forks (of all types). If they publicized this information in the same way that governments and the insurance industry do with automotive crash tests, we’d be much further along. In light of the Specialized recalls especially, I won’t hold my breath for that to happen.

In short, if you insist on riding a carbon fibre or aluminum fork AND value your life, inspect it before every ride. Though that’s good advice for all cyclists, steel gives a much wider margin of error, as your own example above proves. That, and over a century of steel diamond-frame bicycle history.

Excellent dialogue. I have been debating the merits of steel vs carbon for some time. Here’s my experience: I recently purchased a steel cyclocross bike which came with a beautiful lugged steel fork. However, I chose to swap that out and put on an older Ritchey Carbon Comp fork that I had on my cross racing bike. The ride is phenomenal and I have no issues with the fork’s durability, and experienced minimal brake chatter. I have spoken with numerous mechanics from different LBS who feel that the carbon forks are ‘nearly indestructible’ and help minimize the higher frequency road vibrations and add to a comfy ride.

Never the less -I’m probably going to ‘downgrade’ and put back the OEM steel fork based on what I was reading here ( plus the fact that I’m a Retroist at heart and I really like steel forks). It looks better and the pound or so weight penalty is a small price for piece of mind.

Not sure if anyone’s still reading this thread, but as I’m stuck at home with concussion not able to work, drive, exercise or drink alcohol I though I might as well contribute.
I was cycling to work on Wednesday on my old (2009) Boardman Team Carbon road bike along a flat cycle path at 30km/hr. Next thing – bang – I’m trying to get up off the ground, with a bloodied face, confused and disorientated. Passers by on the cycle path called the ambulance I spent the day in the emergency department – CT and MRI of head and neck, fortunately some scrapes and concussion but could have been much worse.
The front fork had failed catastrophically, shearing off where it meets the frame. The problem with this type of failure is the speed that you go down – now warning and not a chance of getting your hands up in front of you to protect your head and face.
I guess some people will say “what does he expect with a bike that old”. The problem is that I – like many people i’m sure – had no idea that such a catastrophic failure could happen without warning. If so, I would have replaced the bike years ago, but it looks like these failures occasionally occur in much newer bikes too.

There is nothing inherently wrong with carbon, but as Luescher explains in the video, not enough is being done to ensure quality control during manufacture of carbon frames, forks and components. There is only one company in the world (Canyon) who CT scan their carbon products as part of routine inspection, and even that may not be enough, since some defects can only be found through ultrasound. This should really be unacceptable.